The trans-border area of the Sudetes between Žďarky and Pstrążna has attracted Prussian/German, Austrian, Czech and Polish geologists since the middle of the 19th century. The history of mapping of this area reflects the scientific development of geological centres in Berlin, Vienna, Prague and Wrocław. This paper presents a description of the oldest geological maps of Lower Silesia in the context of changing knowledge on the Carboniferous and Cretaceous stratigraphy and on the tectonics of the region. On the basis of DEM and field studies the author presents his own geological map of the area of the Pstrążna Elevation together with a description of the local structural geology. A regional structural model is suggested, that explains all the local elevations as having developed in response to a dextral strike-slip activity of the Žďarky-Jakubowice Fault during late Tertiary to Recent times, at an eastern extension of the Poříčí-Hronov Fault Zone., Jurand Wojewoda., and Obsahuje bibliografii
The presented essay was originally published as ''Il samizdat tra dialogo e monologo: Le attività editoriali di Zdeněk Mlynář e la scelta degli interlocutori'' in the Italian online journal eSamizdat: Rivista di culture dei paesi slavi (2010-11, pp. 261-80). This double issue is based on papers given at the conference ''Samizdat between Memory and Utopia: Independent Culture in Czechoslovakia and the Soviet Union in the Second Half of the Twentieth Century,'' which was held at Padua University in late May and early June 2011, and is freely accessible on the periodical website (http://www.esamizdat.it/rivista/2010-2011/index.htm). For its publication in Soudobé dějiny, the author has considerably expanded his essay, particularly after doing research in the Mlynář Papers deposited in the National Archive, Prague. The author concentrates mainly on the research and publishing activities of the politician and political scientist Zdeněk Mlynář (1930-1997) while he was in exile, which he puts into a detailed chronology of his career as a public fi gure. He asks and seeks to answer the general question whether the milieu of samizdat and independent publishing, which developed in Czechoslovakia in the 1970s and 1980s, did or did not leave deep traces also in the structures of the various political activities of those who criticised the state-sanctioned arts and sciences of ''normalisation'' Czechoslovakia. The author points out that Mlynář has today been largely ousted from Czech historical memory, even though he was amongst the leading opponents of the regime after its collapse, and tried to regain a place in Czechoslovak politics. The author recalls Mlynář’s becoming a member of the Czechoslovak Communist Party, his law studies in Moscow in the fi rst half of the 1950s, where he formed a lasting friendship with his fellow-student Mikhail Gorbachev (b. 1931), and last but not least Mlynář as an expert researching the prospects of the socialist political system in the 1960s. He then concentrates on Mlynář’s work during the Prague Spring of 1968, when he became a member of the reformist leadership of the CommunistParty on the side of Alexander Dubček (1921-1992). After the August intervention by the armies of fi ve Warsaw Pact states, Mlynář gradually became disillusioned with the possibilities of continuing reform, and he resigned from the Party leadership. In the early 1970s, he found employment in the Department of Entomology of the National Museum, Prague, and avoided political life completely. Nevertheless, he gradually started to take part in debates with other reformists expelled from the Party about the possibilities of infl uencing developments in Czechoslovakia with the help of left-wing parties in Western Europe. The author discusses Mlynář’s analyses of the situation at the time, the development of his views, and his integration into the nascent dissident movement, which appeared after the founding of Charter 77. A few months later, in June 1977 to be precise, Mlynář emigrated to Austria as a consequence of a smear campaign against the Chartists. The author focuses on Mlynář’s close work amongst Czech exiles, particularly with the increasingly diverse Listy group, which was established by Jiří Pelikán (1923-1999). The group in question was centred on the exile periodical of the same title, which was published in Rome and formed the core of Czechoslovak socialist opposition in exile. In addition, the author focuses on the efforts of Mlynář and his colleagues to win support among Western left-wing circles, particularly in relation to the Italian Communists and Socialists and later the West German Social Democrats. He also takes into account Mlynář’s political essays, which met with a considerable response amongst the public of Western Europe, and the clear shift in opinion from the initial model of a political system with Communist Party hegemony to political pluralism. In this context, the author then gives a comprehensive account of two large research and publishing projects coordinated by Mlynář. The fi rst project, from 1979 to 1982, was entitled ''Experiences of the Prague Spring of 1968''; its participants were almost exclusively Czech sociologists, historians, economists, jurists, and other specialists in exile. The project resulted in almost 30 mimeographed volumes in three language versions (mostly Italian, French, and English), which were distributed by several hundred carefully selected left-wing individuals and institutions in the West, and it culminated in a congress held in Paris. According to the author, this little known project represents one of the most profound and essentially never-published refl ections on the origins, development, and failure of the Prague Spring. The second project, entitled ''Crises in Soviet-type Systems,'' ran from 1982 to the late 1980s, and presented the perspectives of authors from a wider range of central European countries. It resulted in 16 works by Czech, Polish, Hungarian, and East German authors, published by the leading Czech exile publishing house, Index, as small paperback editions in English, French, and indeed German. The number of its subscribers grew to about 2,000. Part of the project was presenting papers at conferences and other international forums. Both of the projects in question, according to the author, demonstrate Mlynář and his colleagues’ persistent orientation to exclusive circles of the political Left in the West, whom, in their efforts to change things in Czechoslovakia, they preferred to the dissidents still in Czechoslovakia.
Metoda zesilování rozmítnutých pulzů vyvinutá Donnou Stricklandovou a Gérardem Mourouem v roce 1985 a oceněná letošní Nobelovou cenou za fyziku způsobila doslova revoluci v konstrukci laserových systémů s vysokým špičkovým výkonem. Maximální intenzita dnešních laserů je až milionkrát vyšší než před 30 lety a jejich využití je celosvětové. Petawattové laserové systémy se uplatňují v celé řadě experimentů z oblasti biologie, fyziky materiálů, urychlování částic či laboratorní astrofyziky. Českou republiku v této oblasti úspěšně reprezentují laboratoře ELI Beamlines v Dolních Břežanech u Prahy, kde jsou v současnosti v provozu dva unikátní laserové systémy terrawatové a petawattové třídy L1 Allegra a L3 HAPLS., The Chirped Pulse Amplification method, developed by Donna Strickland and Gérard Mourou in 1985, which was awarded this year's Nobel Prize in Physics, has revolutionized the field of high peak power laser systems. The maximum intensity of today's lasers is almost a million times higher than it was 30 years ago and their application is worldwide. Experiments using petawatt laser systems range from biology, material physics, and particle acceleration to laboratory astrophysics. The Czech Republic is successfully represented in this field by the ELI Beamlines facility located in Dolní Břežany near Prague, which houses two unique terawatt and petawatt class laser systems L1 Allegra and L3 HAPLS., Lucia Koubíková., and Obsahuje bibliografické odkazy
This contribution gives a brief description of the characteristics of spectral lines formed in the solar chromosphere in the visual range and its continuum in the visual, millimetre, and sub-millimetre (mm-submm) spectral range. The contribution reviews processes responsible for continuum radiation of the limb in the visual range and continua in the mm-submm spectral range. The spectral lines of sodium doublet Na I D1 and D2 are not genuine chromospheric lines since their cores are formed predominately by resonant scattering of radiation from the upper photosphere. Therefore, the cores of Na I D1 and D2 provide information only about chromospheric velocities. An occurrence of the doublet Na I D1, D2 together with helium lines with large excitation and ionization potential indicates an intricate thermodynamic structure of the chromosphere. As numerical simulations indicate, the chromospheric internetwork comprises of cooler cavities surrounded with hotter sheets allowing the occurrence of spectral lines over a large range of excitation and ionization potentials. The contribution accentuates the large diagnostic potential of the mm-submm continua of the chromospheric spectrum. It will be fully exploited after finishing of the ALMA array for the study of the chromospheric fine structure with large angular and temporal resolution., Príspevok podáva stručnú charakteristiku čiarového spektra slnečnej chromosféry vo vizuálnej oblasti a jej spojitého spektra (kontinua) vo vizuálnej, milimetrovej a submilimetrovej (mm-submm) oblasti. Príspevok predstavuje procesy tvoriace vizuálne kontinuum pozorovatel'né na limbe a kontinuá v mm-submm oblasti. Čiary sodíkového dubletu NA I D1 a D2 nie sú v pravom slova zmysle chromosférické, pretože ich jadrá sú tvorené hlavne rezonančným rozptylom žiarenia hornej fotosféry, a preto poskytujú informáciu iba o rýchlostných poliach v chromosfére. Výskyt dubletu Na I D1 a D2 spolu s čiarami hélia s veľkou excitačnou a ionizačnou energiou naznačuje zložitú termodynamickú štruktúru chromosféry. Ako ukazujú numerické simulácie, chromosféra sa v oblastiach mimo magnetickej siete skládá z chladnejších oblastí obalených horúcou látkou, čo umožňuje vznik spektrálnych čiar vo vel'kom rozsahu excitačných a ionizačných energií. Príspevok poukazuje na vel'ký diagnostický potenciál kontinuí v mm-submm oblasti spektra chromosféry, ktorý bude naplno využitý po dokončení rádioteleskopu ALMA pri štúdiu jemnej štruktúry chromosféry s vel'mi vel'kým uhlovým a časovým rozlíšením., Július Koza., and Obsahuje bibliografii
Cadmium in the dose of 1 mg/animal/day was administered to guinea-pigs in the form of CdCl2 dissolved in drinking water during short-term (5 weeks) and subchronic (12 weeks) experiments. Both the control and cadmium-treated groups were divided into two subgroups, according to low (2 mg/animal/day) and high (100 mg/animal/day) vitamin C intake. Subchronic cadmium treatment caused copper deficiency indicated by a dramatic decrease of copper concentration in the liver and serum and by its moderate decrease in the testes and brain. Cadmium significantly increased zinc concentrations in the kidneys during the whole experiment and decreased the level of zinc in the serum after subchronic cadmium treatment. In the control groups, the levels of zinc and copper in the serum were lowered after 5 weeks of high vitamin C doses. High doses of vitamin C in cadmium-treated guinea-pigs decreased the levels of copper in the testes, brain and serum. These observations suggest that cadmium intake in relatively high doses might potentiate the development of copper deficiency, and high doses of vitamin C aggravate, to a certain extent, copper depletion in some important organs and serum of guinea-pigs.
Holanďan Christiaan Huygens významně přispěl k rozvoji mechaniky a optiky v návaznosti na problémy, které řešila astronomie. Je vynálezcem kyvadlových hodin, nejpřesnějšího časoměrného přístroje doby umožňujícího poprvé stanovení zeměpisné délky plujících lodí., The article deals with the life and work of Dutch astronomer, physicist and mathematician Christiaan Huygens. Describing his extensive scientific work, we start with his activities in the field of observational astronomy (e.g. the discovery of the rings and moon of Saturn and the summary of the existing knowledge of the planets in his publication Cosmotheoros). His discovery and quantitative description of centrifugal force contributed significantly to solving problems describes in Newton´s Principia. Huygens is also well-known as a technician and technical designer. He constructed the first pendulum clocks. Last but not least, we describe his work on the impact of solid bodies, when he reflected on the work of R. Descartes and J. Marek Marci., František Jáchim., and Obsahuje seznam literatury
Sofia Kovalevskaya was not only a great Russian mathematician, but also a writer and advocate of women's rights in the 19th century. After concluding her sexondary schooling, Sofia was determined to continue her education at the university level. She travelled to Heidelberg to study mathematics, but discovered there that as a woman she could not graduate. In 1870 she moved to Berlin to study with Karl Meierstrass, in 1874 she was granted a Ph.D. from the Göttingen University. In 1883 she received an invitation from Gösta Mittag-Leffler to lecture at the University of Stockholm. Sophia's most famous work is on the theory of partial differential equations, and on the rotation of a solid body about a fixed point. Sophia died very young, at the age of 41, from pneumonia., Ivo Kraus., and Obsahuje bibliografii
Fyzikálne vzdelávanie v rámci prírodovedného a technického vzdelávania je vo vyspelých krajinách považované za dôležité. Pritiahnuť mladých ľudí a inšpirovať ich učiteľov pri vzdelávaní v týchto školských predmetoch je viacročnou ambíciou aj autorov tohto článku. V tomto článku sa zameriavame na využitie lacnej vývojovej dosky s jednočipovým mikropočítačom Arduino Uno R3 pri konštrukcii jednoduchého hudobného zariadenia - syntetizátora - a jeho následného využitia vo výučbe. Samotná konštrukcia zariadenia môže byť námetom na časovo náročnejšiu bádateľskú aktivitu (v zmysle IBSE - Inquiry Based Science Education). Súčasťou článku sú aj námety na ďalšie bádateľské aktivity, od časovo náročnejšej, venovanej konštrukcii syntetizátora, až po jednoduchšie, zrealizovateľné v rámci jednej vyučovacej hodiny., Physics education is considered to be important in science and technology education in developed countries. Attracting young people and inspiring their teachers for these subjects is a long-term ambition of the authors of this article. In this paper, we focus on using a low-cost development board with a single-chip microcomputer Arduino Uno R3 in the construction of a simple music device - a synthesizer - and its subsequent use in teaching. The design of the device itself can be the subject of a time-consuming inquiry-based activity (in terms of IBSE - Inquiry Based Science Education). This article also includes suggestions for further inquiry-based activities, from the more time-consuming construction of the synthesizer to simpler ones, that can be achieved within one lesson., Martin Hruška, Miriam Spodniaková Pfefferová, Stanislav Holec., and Obsahuje bibliografické odkazy